Emergency-brake for hoist-engines.



H. N. GOVELL.

EMERGENCY BRAKE FOR HOIST ENGINES.

2 5HEETS-SHEBT 1.

mmvro/s Lind! BY flue AATTOHNEYS W/TNESSES COLUMBIA FLANOUKAPH C0.,Wn r|lNGTON, D4 c.

H. N. COVELL.

EMERGENCY BRAKE FOR HOIST ENGINES.

APPLICATION FILED NOV. 30, 1907.

1 ,01 3, 1 3 1 Patented Jan. 2, 1912.

2 SHEETS-SHEET 2.

INVENTOH WITN ESSES ATTORNEYS COLUMBlA PLANOGRAPH co, WASHINGTON. D, c.

on Ten STATES PATENT OFFICE- HARRY N. COVELL, OF NEW YORK, N. Y., ASSIGNOR T LIDGERWOOD MANUFACTUR- ING COMPANY, A CORPORATION OF NEW YORK.

I EMERGENCY-BRAKE FOR HOIST-ENGINES.

Patented Jan. 2,1912.

1907. Serial No. 404,480.

Specification of Letters Patent.

Application filed November 30,

gear wheels 4:, 6 and 7 may be inclosed in a gear casing. By any well known form of connections, such as worm or spur gearing at 9, motion is transmitted from axle 8 upon which the gear 7 is carried to a vertical shaft passing up. through support C and provided at the top with fly ball governor 10. Thus, through gear wheels and connections 4, 6, 7 8 and 9, the fly ball governor 10 is actuated by the drive shaft B, the gearing being adapted to drive the governor at such a rate of speed that the fly balls will remain in a normal or lowered position until the speed of the drive shaft B exceeds a predetermined limit of safety; as the limit of safety is exceeded the fly balls will assume an elevated position for a purpose hereafter more fully to be described.

Connected with the fly ball arms by rods is a collar 12 movable on the upright governor shaft and bearing in an annular groove in its surface the ring end of the upper arm of a bell crank lever 14.- Member 14 is pivoted at its angle at 15 at the upper end of angular arm 5, and is connected at the end of its lower arm with a rod 16 which in turn extends and is connected to one arm of a second bell crank lever, 17 pivoted at 18 on a suitable support D mounted on 2. The second arm of crank lever 17 is provided with hook member 19 normally engaging with a pin 20, adjacent to the center of a counterweighted lever arm 21 pivoted at itslower end 22 on support D,- said hook member retaining the arm 21 in an upright position. The lower end 22 of arm 21 is enlarged and resting thereon is a roller bearing 23 mounted adj a cent the center of a trip jaw member 2 1 pivoted at its upper end 25 on support D. Adjacent to the lower end of 2 1 a hook jaw 26 engages with a pin 27 projecting from the counterweighted arm 28, and serves to retain one end of the arm 28 in an elevated position. Arm 28 is secured at its lower end to brake shaft E and is adapted to operate the shaft to set the engine brakes when its elevated end is released from the hook jaw 26 and is depressed by the counterweight 29; counterweight 29 is adjustable on arm 28 to regulate the force with which it is desired to depress the arm, and is retained in any set position thereon by catch member 30 engaging with one of the series of notches 31 on the arm,

To all whom it may concern:

Be it known that I, HARRY N. CovELL, a citizen of the United States, and a resident of the borough of Brooklyn, in the city of 5 New York, in the county of Kings and State of New York, have invented certain new and useful Improvements in Emergency-Brakes for Hoist-Engines, of which the following is a specification.

It is the purpose of my improved device to provide an emergency brake to control the operation of a hoist engine when the rate of descent of a load in connection therewith exceeds the predetermined limit of safety. I provide a device embodying simplicity of design and construction, and automatic operation, at the same time provid ing additional means for operation by hand should such become necessary. It is to be noted that my device is adapted to stop the engine with an absence of shock or jar detrimental to the machinery in all its parts.

I do not desire to restrict myself to the exact application of my invention as shown in and described in connection with the drawings herewith, but my invention consists in the construction, arrangement and operation of parts as set forth in and falling within the scope of the claims hereto appended.

Like characters of reference denote like arts in all the figures.

Figure 1 represents a view in front elevation of my improved device, hidden parts being shown in broken lines; Fig. 2 represents a view in rear elevation of my improved device, hidden parts being shown in broken lines.

Turning to Figs. 1 and 2, the letter A denotes the hoisting engine bed plate which is provided with ribs or flanges 1, 2 and 3, integral therewith, which support a bearing in which the drive shaft B is carried, which is adapted, by any suitable means, to revolve as the load operated upon by the hoist engine descends, and at a rate of speed varying with that of the descent of the,load; mounted on said shaft B is agear wheel 4. A suitable support C mounted on 3 is provided with an angular arm 5, upon which arm is mounted a second gear wheel 6 intermeshing on one side with gear wheel 4, and on the opposite side with a third gear wheel 7 secured to the end of an axle 55 8 which passes through support 0. The

From the arrangement of parts above described it will be seen that when the ,fiy balls of governor 10 are elevated the end 13 of the upper arm of crank lever 14 will be raised, as will also its lower arm, and through rod 16 the crank lever 17 will be swung upward on its pivot 18 to release pin 20 from hook member 19; the arm 21 will thereupon fall, turning on the pivot at its enlarged lower end 22 and that end will force up the trip jaw member 24, disengaging the hook jaw 26 and pin 27 and allowing of the depression of the arm 28 and the setting of the engine brakes.

Mounted on the support D is a tackle pulley 32 hearing chain tackle attached to the end of the arm 28 for the purpose of raising the arm after it has been depressed. Secured to the lower end of the trip jaw member 24 is a rope member passing over the pulley 33 for the purpose of disengaging 26 and 27 by hand should it become necessary to operate the brake setting device in this manner.

Mounted on the rear of the support C is a dash pot 34 provided with a piston and piston rod, the rod being pivoted at its outer end on the upper end of a lever arm 35 formed integral with the arm 28 and extending from its lower end; by this means when the arm 28 is depressed the arm 35 forces the piston into the dash pot 34L and a cushion is formed for the fall of arm 28 and the setting of the brakes in order that it may be done without sudden jar. The dash pot 34 is provided with an air cock 36, to regulate the escape of air, and the cock is preferably inclosed in a locked box 37 to prevent tampering therewith. The lever arm 35 when raised by the fall of 28 also elevates a weighted arm 38 resting thereon, which then operates electric current control means 89. The electric current control means 39 .may be of any desired form and is adapted to'automatically and instantaneously turn off the current from the motor when the brake device is used on an electric hoist, or, when used in connection with a steam operated engine, it is adapted through suitable connections to operate any desired form of mechanical means for shutting off the steam at the engine throttle. An auxiliary spring controlled switch 40, released by the elevation of stud 41 mounted on arm 85, may also be used to control the electric current which operates to shut ofl the motive power from the motor or engine.

The operation of my improved brake-setting device above described is as follows: The fly ball governor through the gearing and connections being adapted to revolve in an inoperative position with lowered arms when the speed of the drive shaft is below or equalto a predetermined limit of safety, the arms thereof will become elevated when the speed exceeds the limit of safety. The crank levers and connections will operate to release the counterweight arm 21 which in turn operates to release the counterweight arm 28, the fall thereof being cushioned, which operates the engine brake. At the same time the electric cur rent control means and auxiliary switch are automatically operated to shut off the motive power of the hoisting engine at the same moment that the brake is operated. After operation the arm 28 is raised to an operative position by the hand tackle or by any suitable means, thereby releasing the engine brake, the arm 35 assumes its lowered position allowing the weighted arm to fall and depressing the auxiliary switch in order that the motive power of the engine may thereby be turned on as the brake is released. The various hook lever arms and pins are engaged, and the fly ball arms of the governor having assumed their normal lowered position the device is ready for operation should the speed of descent of a load again exceed the predetermined limit.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a brake-setting device, in combination, a drive shaft, a brake shaft, means for operating the brake shaft, said means comprising a weighted arm member, a governor member adapted to operate to release said arm member, a hook, and a second arm in engagement with said hook adapted to be released upon the release of said first arm, and means for controlling the fall of said second arm when released, said control means comprising a third arm adapted to be elevated upon the fall of said second arm.

2. In a brake-setting device, a drive shaft, a brake shaft, a governor mechanism, a gravity lever, a latch to hold the same, said latch being operated by the governor mech anism, a cam operated by the gravity lever, a gravity brake lever, and a latch for holding said brake lever, said latch being operable by the cam.

3. In a brake-setting device, a drive shaft,

a brake shaft, a governor mechanism, a'

gravity lever, a latch to hold the same, said latch being operated by the governor mechanism, a cam operated by the gravity lever, a gravity brake lever, a latch for holding said brake lever, said latch being operable by the cam, and controlling means operated by the brake lever.

4. In a brake-setting device, a drive shaft, a brake shaft, a governor mechanism, a gravity lever, a latch to hold the same, said latch being operated by the governor mechanism, a cam operated by the gravity lever, a gravity brake lever,

said brake lever, said latch being operable a latch for holding the second hook and by the cam, and means for regulating the fall of the gravity brake lever.

5. In a brake-setting device, a drive shaft, a brake shaft, a governor mechanism, a gravity lever, a latch to hold the same, said latch being operated by the governor mechanism, a cam operated by the gravity lever, a gravity brake lever, a latch for holding said brake lever, said latch being operable by the cam, means for regulating the fall of the gravity brake lever, said means comprising a retarding device acted upon by an arm on the gravity brake lever.

6. In a brake-setting device, in combination, a drive shaft, abrake shaft, a governor, gear connections between the drive shaft and the governor, a pivoted hook, connections between the governor and the hook, an elevated arm engaging with the hook adapted to be released upon the operation of the governor, a second pivoted hook adapted to be swung on its pivot upon the release of said elevated arm, a weighted second arm mounted on the brake shaft engaging with adapted to be released and to operate the brake shaft upon the swinging of said second hook on its pivot.

7 In a brake-setting device, in combination, a drive shaft, a brake shaft, a governor, gear connections between the drive shaft and the governor, a pivoted hook, connections between the governor and the hook, an elevated arm engaging with the hook adapted to be released upon the operation of the governor, a second pivoted hook adapted-to be swung on its pivot upon the release of said elevated arm, a weighted second arm mounted on the brake shaft, engaging with the second hook and adapted to be released and to operate the brake shaft upon the swinging of said second hook on its pivot, means adapted to control a supply of power agent, means for controlling the fall of said second arm, and means for operating said power agent controlling means and said fall controlling means upon the fall of said second arm.

In testimony whereof I have hereunto signed my name to this specification in the presence of two subscribing witnesses.

HARRY N. COVELL.

Witnesses:

C. W. ADAMS,

CHAs. H. TELLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

